The Wanderers' skipper levelled in superb style - his 100th league goal - this after not training all week.
Davies, 33, who suffered concussion against Arsenal last week, played three times at Under-21 level but has never got a senior cap.
And Coyle said: "It has probably passed him by now but how he never got an opportunity to play for his country is beyond me. He is not underrated by me.
"Sometimes people give him a name and they see nothing more than that. But he has so much more.
"He is always a threat. He has tremendous qualities as a footballer and as a man."